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  • PTFE Membrane Filter

    What is PTFE?

    Johnson Test Papers’ PTFE membrane filters are made of PTFE (polytetrafluoroethylene). It is a microporous film laminated with fabric and paper. They are one of the newer types of filter media applied to extensive industries including pharmacy, biochemistry, microelectronics, and laboratory materials etc.

    PTFE membranes are particularly suited for aggressive media, since they are chemically inert towards aqueous and organic solutions as well a towards concentrated acids and bases (pH 1 - 14), which other filter types are not resistant against. PTFE membranes are used for liquid clarification of corrosives, solvents, and aggressive fluids. Effective sample filtration is critical to prevent equipment damage. GE’s PTFE hydrophobic membrane filters are also suitable for air and gas sterilization because of their ability to capture aqueous aerosols.

    They allow the passage of air and gas particulates and do not get clogged up by humidity. When intended for the filtration of aqueous solutions, they need to be pre-wetted with ethanol or methanol prior to use in order to permit water penetration. PTFE membrane filters are ideal for gas filtration. These membranes are permanently hydrophobic by their composition, thus the pressure for filtration of aqueous solutions has to be higher than the breakthrough pressure. Johnson Test Papers’ PTFE membranes can be used at temperature up to 130 °C

    PTFE membrane filters are available in both hydrophilic and hydrophobic configurations.

    For additional information on OEM specific applications, Johnson Test Papers has the product breadth and flexibility to meet your needs, as well as the quality standards to help ensure your success. Contact us to discuss application requirements, request free product samples and order products.


    • Filtration of strong acids and aggressive solutions
    • Venting applications
    • Phase separations
    • Aerosol samplings, sterilization of gases and sterile containers
    • Sterilization of gases and events of sterile containers
    • Protection of haemodialysis against blood and humidity


    • PTFE membrane is a microporous film supported with a layer of polyester or polypropylene
    • The PTFE membrane can effectively filtrate microorganism and other particulates
    • Wide chemical compatibility (pH 1 - 14)
    • High temperature resistance
    • Low starting resistance
    • Hydrophobic membrane
    • Resistance against most of organic solvents and aggressive liquids
    Sterilisation Compatability Thickness Extractable Wettability Maximum Operating Temperature Pore Size Range
    Sterilization: Autoclave, ɣ-radiation (25 KGɣ) or with ethylene dioxide Thickness: 160 - 260 μM Extractable: <1% Wettability: Hydrophobic Maximum operating temperature: 130°C Pore size range: 0.1 to 5μM
    Technical Specification
    Product Code Pore Size (μM) Minimum Bubble Point (psi) Typical Flow Rate (mL/min·cm²@0.07Mpa)
    PTFEM047020 0.22 0.1 10
    PTFEM047045 0.45 0.05 25